Adjustable back rest for chairs



' P. w. oLsoN' ADJUSTABLE BACK REST FOR CHAIRS sept. 11, 1928.

Filed Feb. 18, 1927 Patented Sept. 11, 1928.

UNITED STA BERCY W. OLSON, OF ST. PAUL, MINNESOTA, ASSIGNOR TO WILLIAM S. FERRIS, OF ELKHART, INDIANA, TRADING AS THE DOMORE CHAIR COMPANY. v

" ADJUSTABLE BAOK REST FOR CHAIRS.

`Application filed February 18, 1927. Serial No. 169,179.

This invention relates to improvements in c adjustable back rests for chairs, and 1t consists of the matters hereinafter described v and more particularly 'pointed out in the appended claims. f

The primay object of the invention is to provide a simple back rest construction for chairs which may be readily adjusted into that position most desired by the occupant of the chair.

A further object of the invention is to provide a back rest which includes substantially upright side arms, slotted at their top ends and pivoted at their bottom ends to the chair fra-me to provide the desired adjustment therefor and also to provide in connection with the slotted ends of said arms, plate members extendingV forwardly therefrom and adjustable longitudinally thereof, said plate members having pivoted thereto, the ends of a back rest member.

These objects of the-invention as well as others, together with the many advantages thereof, will more fully appear as I proceed with my specification.

In the drawings:

Fig. 1 is a perspective view of a chair embodying the preferred form of my invention.

Fig. 2 is a perspective view on an enlarged scale of those parts shown in the upper right hand corner of Fig. 1, the back rest member being omitted to more clearly show the construction of said parts. Y

Fig. 3 is a detail horizontal sectionalview on an enlarged scale as t-aken on the line 3-3 of Fig. 2.

Refering now in detail to that' embodiment of the invention illustrated in the accom-- anying drawing, 1 indicates as a whole in dotted line what has now become known as a correct posture chair. It includes a rectangular seat frame 2 suitably mounted upon supporting legs 3 and carrying a seat 4. In such a chair the seat frame is made of edgewise disposed strap Viron and pivotedV as at 5 to the rear end of each side member 6 thereof is a substantially upright side arm 7 Associated with each arm is a curved brace 8 also made of strap iron and said brace is pivoted at its top end to the arm 7 and at its bottom end carries an attaching device 9 to enter any one of a number of holes 10 in the side member of the seat` frame. By inserting the device 9 through the proper hole 10 thefdesired angular position of the side arm may be readily attained.

Preferably the top ends of they side arms A`are offset inwardly toward each other as at 11 and in each offset end is provided a longitudinally extending slot 12. Associated with each offset top end 11 on the inner surface thereof is a forwardly extending plate like member 13 arranged at a right angle to said end of the arm. Said plate is so arf ranged with respect to said arm end as to be adjustable longitudinally thereof without changing its right angular position. To this end, I form on the plate at its top and bottom edges, offset portionsy or ears 14 which so engage certain edgesv of the arm ends as to maintain the desired angularity of the plate member. Invthis instance I find it convenient to` so arrange these ears as to engage the front endges of the associated arm ends but they may also be so dis posed as to engage in the slot 12. Each plate is attached to its associatedarm end by a bolt 15 which passes through the rear end part of said plate and through the slot 12 in said arm end, a winged nut 16 being threaded upon the bolt to lock or clamp the plate in place. Pivoted to the front end of each plate is an angle or L shapedy bracket 17 having a rearwardly extending leg 18 and an inwardly extending eared portion 19. The leg 18 of said bracket is pivotally connected to the forward end of the plate 13 by means ofa rivet 20. The eared portion 19 of each bracket 17 is attached in any suitf able manner to the rear side of each end of a back rest member 21 which is transversely elongated and is bowed rearwardlyas shown in Fig. 1. Preferably this back rest member is padded on its front side to be more comfortable for the occupant.

Itis apparent that upon loosening the nuts 16, the plates 13 together with the back rest member 21 may be adjusted vertically of the arms into the. desired height above the seat, after which the wing nuts are again tightened up. When the chair is occupied, the back rest member will swing about the rivets 20 as an axis to lit itself to the back of the occupant.

The back restabove described is a simple construction and may be produced and assembled at a low cost. `It is readily manipulated to llocate the back rest member in that position most comfortable to the 0ccupant of the chair.

lVhile in describing my invention, I have referred to certain details oi construct-ion as Well as form and arrangement of the parts thereof, I do not Wish to be limited thereto except as may be pointed out in the appended claims.

I claim as my invention: l. An adjustable back rest for chairs ineluding a side arm having a longitudinal slot in one end thereof, a plate associated with each arm end and having parts to engage an edge of the arm end to hold the plateat a right angle thereto, means passing through said plate and slot-ted arm end to through said plate and slot in said arm end to secure said lplate thereto and ay bracket pivoted to the front end of said plate and tolvvhich a back restV member is attached. In testimony whereof,v I have hereunto setmy hand, this lll dayy of `February, 1927.

PERCY W. OLSON. 

